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There are n persons (n ge 3), among whom...

There are n persons `(n ge 3)`, among whom are A and B, who are made to stand in a row in random order. Probability that there is exactly one person between A and B is

A

`(n-2)/(n(n-1))`

B

`(2(n-2))/(n(n-1))`

C

`2/n`

D

none of these

Text Solution

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The correct Answer is:
B, C
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